Manually operable control levers have long been used in vehicle control systems. They can be used to set, for example, the speed, the steering, an operating function or a gear setting of the vehicle. The control lever can be a joystick for controlling a loader tool. The vehicle may be an agricultural vehicles, such as a tractor, a harvesting machine, a combine harvester, a forage harvester, a self-propelled sprayer, but also an industrial vehicle, such as a construction vehicle, a bulldozer, a road grader, a backhoe excavator, a loader vehicle, a tipper lorry, a crane, or a telescopic loader.
Furthermore, “force feedback” is known from simulator technology where it generally serves to realistically represent forces to which operating elements are subjected, the forces occurring during the operation of an actual machine and having to be applied or overcome by the operator. In a force feedback system, an actuator applies a force to a control lever. The control lever, which generates an electrical signal, can be subjected to a force from the actuator so that the control lever has an operating characteristic customary for the particular type of control lever.
In many vehicles, the operating elements are usually connected mechanically to the machine part adjusted by them. For example, the steering wheel is connected to the steering linkage via the steering shaft. If such a mechanical connection is omitted because of an electronic control of the particular component, then a corresponding feedback to the operator about the states of the machine part and of the machine/vehicle to be simulated is lacking. In such a case, simulator technology is used to cause an actuator to apply a force to the control lever, and the actuator is controlled by a control unit, such that an operating characteristic customary for the control lever can be produced. By this means, an operation, which is as realistic as possible, of the particular function controlled by the control lever is simulated for an operator.
Warning display elements may supply visual or acoustic signals to the operator during the operation of the vehicle. For example, warning lights are primarily provided which indicate a critical state of the vehicle, such as excessive engine oil or coolant temperature.